What are they nade of?
Bricks are made of different materials depending on the type of brick, but in general their components envolve ceramic, mud, lime, quartz, rock, minerals, water,clay, slate, concrete, etc.

What are they used for?
Bricks are used in construction, mostly for making walls.

How many types of brick are there?
There are 4 types of brick: Mud bricks, dry pressed bricks, extruded bricks and calcium silicate bricks.

What is the meaning of brick laying techniques?
Brick laying techniques are the different ways in which you can organize bricks in order to make a construction.

Describe two brick laying techniques with their advantages and disadvantages.
One way to layout bricks is in the stretcher bond way, this has the simplest pattern but it can only be used in a wall that has the thickness of half a brick.
Stretcher.png

Another way to layout brics is in the Rat-trap bond which consists of rowlocks and shiners. This gives the wall an internal cavity and makes it a very economic way to organize the bricks.
120px-Rat-trap_bond.svg.png

In my opinion, brick is a very good option to make a construction both strong and beautiful. Besides this, it has many advantages because it is easy to trasport, it's economic and it's very simple to do the layout. That's why brick can be used in private and public spaces and the different types of bondings can be addapted the different needs that the space of the construction requires.